Hydraulic control for trail builder



Jan. 2,` 1940.

L. O. BIRD ET AL HYDRAULIC CONTROL FOR TRAIL BUILDER 5 shets-sheet 1 Filed June l, 1955 lllllllllx Jan. 2, 1940. l.. o. BIRD er AL HYDRAULIC CONTROL FOR TRAIL BUILDER Filed June 1, 1935 5 Sheets-Sheet 2 A I nwnlors JUL 2 1940- l. vo. BlRD Er AL 2,185,179

l HYDRAULIC con'rRoL PoRTRAIL BUILDER Filed June 1, 1955 5 sheets-sheet s o. BIRD ET AL HYDRAULIC CONTROL FOR TRAIL BUILDER Jan. 2, 1940.

Filed June 1, 1955 5 Sheets-Sheet 4 Jan. 2, 1940. l.. Q BIRD 'ET AL HYDRAULIC CNTROL FOR TRAIL BUILDER Filed June l, 19255 5 Sheets--SheeiI 5 111 lllllfap1lrh= rllllllllflllll Patented Jam, 2, 1940 Ik!! 0. Bird, Glendale,

Los Anteles, Calif.;

saidBil'd' am Edward P. Drake,

said v Drake assignor to Application June 1', i935, serial No. 24,562 1oclaims. (ci. :rz-144).

This invention relates to new and useful improvements in trail builders, bulldozers, back llers, and the like and more particularly to a hydraulic control mounting said hydraulic control system and the implement on a tractor, and inasmuch as there is common subject matter it isa continuation of improvements in the type of controls and mount" ings illustrated, described and claimed in appli?l cations executed by Len O.` Bird, the above mentioned joint inventor in the present application, and iiled as follows:

Filed Oct. 30, 1931, Serial No.'572,044, Pat. No.

system and to the manner oi 1,991,781; filed Dec. 27, 1932, Serial N0. 648,893,v l5 Pat. No. 1,964,617; led Jan. 3, 1933, Serial No..

649,921, (since abandoned); nled Feb. 1, 1933, Serial No. 654,577 (since abandoned); filed Aug. 8,1933, Serial No. 684,215, Pat. No. 1,976,597 ;`led Nov. 6, 1933, Serial No. 696,786, Pat. No. 1,977,817. n p Of the manifold objects of this invention the principal one is the provision of hydraulic controls for a trail builder by means of which the blade may be, raised,rand lowered for controlling the inoperative and operative positions, tilted to control the angle of the cutting edge with respect to the ground surface, and angled from the' transverse position to'cast the removed material to either side, while the tractor is in motion. y

lA further object is theprovision of a trail y builder in which the means for raising, lowering an d tilting the blade as well as the means for angling same, consist of two hydraulic power units connected directly or through suitable levers to the implement or blade and associated with a valve device which controls each power unit through anA independent -iiuid column insuringl positive action of each power unit, eliminatingthe counter shaft which has to be used when the power units are connected in series for opera- 40 tion through a common column of fluid as has heretofore been the case, also a countershaft control limits the versitality of the system to controlling .only the oper tive -and inoperative positions and requiring an independent means 45 for tilting same. l

Another object is the provision of anI implement of the character described in which the hydraulic control system is equiped with equalizing or compensating Vmeans consisting of cyl- 50 inder and piston 'assemblies operatively interposed between the tracklayer frames andthe engine bed, and connected ito the power unit conduits, to utilize the relative movement'between the engine bed and the tracklayer frames 5 5l for displacing fluid between the compensating cylinders and the power units to maintain the blade in the set position regardless ofany uneven surface traversed by the tractor.

. A furtherpobject is the provision ofl an implement of the character described in which the 5 pusher arms carrying the blade member are provided' near the rear ends with auxiliary hydraulic jacks associated with the control system to act simultaneously with the power units for tilting theblade by raising one pusher arm l0 and lowering the other on an even keel to prevent distortion of the implement.

Another object is the provision of a master cylinder yand valve arrangement which may be installed in any implement using two or more power units for controlling the degree and class of operation to render said implement capable l of performing the above outlined functions.

A further object is to provide suitable mountings and connections for the numerous types of implements to advantageously utilize the meritorious characteristics of the control system in each individual case with maximum eiciency and economy.

With these and other objects in view the invention consists in the combination, correlation, and construction, of parts, members and fea'- tures which will be described in the specification 'and will be finally pointed out in the claims.,

Referring to the drawings: y Figure 1 is a plan view of a device embodying our invention.

Figure 2 is a rear end elevation of Figure 1,A illustrating the mounting of the device on a tractor. l v 35 Figure 3 is a' semidiagrammatic view of the hydraulic control system. illustrating the master y cylinderin section as indicated by line 3-3 `in Figure 5.l Figure 4 is a section approximately on line 4--4 40 of Figure 5 illustrating the control valve in detail. Figure 5 is a section on line 5--5 of Figure 4. Figure 6 is a section on line E-B'of Figure 4. Figure 7 is a diagrammatic view of the hydraulic system in which the parts and passages within the .valveand master cylinder are represented by means of tubing. connections to' facilitate the v illustration of the flow of fluid.

Figure 8 is a detail of the raising and lowering valve in one of the operative positions.

Figure 9 is a detail of the tilting valve in one of the operating positions. AFigure 10 is a plan view of an implement similar to that shown in Figure 1 illustrating means for connectng-'the pusher arm to the tracklayer vu frames of the tractor and 'additional hydraulic form of mounting illustrating the hydraulic control system diagrammatically.

Figure 14 is a diagrammatic flow chart of the hydraulic control system shown in Figures 11, 12, and 13.

Figure 15 is a diagrammatic ow chart of a hydraulic control system in which the master cylinder is eliminated.

The objects outlined above are attained by the preferred and modied forms of embodiment of the invention shown in the drawings, which in a generic sense consists of an implement comprising a pair of pusher arms connected at the rear ends either Vto the draw bar or the tracklayer frames cfa tractor and carrying at the forward ends a blade element which may be of the rigid transverse type, the tltable type, the angling type or `adapted for performing any two or all three of these functions singly or in combination, manually or hydraulically, a hydraulic control system comprising a pair of hydraulic Ypower units mounted on suitablebrackets secured either to the engine bed or the tracklayer frames of the tractor, means for supplying duid under pressure in individual columns of identical volumes to the hydraulic power units to facilitate positive action of said power units, equalizing or compensating means for`dispensing uid to the power units in proportion to the tilting or swaying of the tractor for maintaining the blade element in the-set position, auxiliary hydraulic pusher arm jacks associated with the control system to operate simultaneously with the power units for tilting the implement on an even keel, and valve means for controlling the hydraulic system from the operators station.

Referring to Figures 1 to 13 inclusive:

In` a more specic sense, the preferred form of the control means for an implement exemplified in the accompanying drawings in a practical form of embodiment, is shown as comprising the usual blade member I rand a pair of rearwardly extending pusher arms 2 connected as at 3 to the draw bar 4 of tractor 5.

In Figures 10, 11, 12, and 13 the pusher arms 2a are shown connected to tracklayer frames 5 of the tractor 5 through means permitting vertlcal movement upon actuation of the hydraulic jacks 1, and l1 which be described in more detail hereinafter.

The hydraulic control system consists of a pair of hydraulic cylinders 8 and 8' pivotally mounted, as at 9, on brackets I0 secured to-the sidesof engine bed II of tractorv5, as at I2, a pair of bell cranks I3 pivotally mounted on brackets lfas shown at I4, are connected to piston rods I5 and I5', as at I6, and tothe blade l through links l1. f

v "In some cases, especially in heavy duty implements, it is advisableto mount the brackets I0 carrying the cylinders 8 8' and the bell cranks I3'onvv the traeklayer frames of the tractor since the tracklayer frames; are adapted to rcarry a greaterload than the engineA bed.V Figure 11 i1- vlpstrates how thebrackets Il! may on haped supportsV I8 which straddle the track- 'layers' andfastenfto thesides ,of the traeklayer frames 6 Vby means of screws, bolts, or rivets, for

whichv holes I3 are provided. The supports I8 may be reinforced by means of braces 23.

'I'he operation of the pistons 2| and 2|' within cylinders 8 and 8' is controlled by a master cylinder 22 which is divided into three chambers, the power chamber 23 and the chambers 24 and 25, for controlling cylinders 8 and 8', respectlvely,

Y by means of the closures 26. Apiston rod 21 having the pistons 28, 23, and 30 arranged thereon to function within chambers 23, 24, and 25 respectively. Closures 26 are provided with pressure packing 3| at the points where piston rod 21 passes through.

At the power chamber end of the master cylinder 22 a valve 32 is located; said valve comprises a pair of plugs 33 and 34 individually operated by means of handles'or levers 35. The

plug 33 is used for raising and lowering the implement and the plug 34 for tilting same.

Includedinthesystcmisareservoirtank and pump 31 of any conventional type associated in the usual manner with the power takeoffk on the tractor. The pressure side of pump 31 communicates with the valve chamber 38 through conduit 3Q, then through Pille 01' conduitA 4l with g5 valve chamber 4I and then through conduit 42 with tank 36.

The valve plugs 33 'and 34 are provided with fan shaped ports 43 to direct the fluid under pressure in three selective directions, and the return ports 43'. Whenthe plugs 33 and 34 are in the neutral or inoperative position the ports 43 are aligned to elect by passing or circulation of uid from the tank 35 through conduit 44, pump 31, conduit 33,-port 43 of plug 34, pipe 4I, port 43 of D lug 33 and conduit 42 back into tank 3S.

The valve chamber 4I communicates with the opposite ends of the power chamber 23 through the diametrically opposed ports 45 and 46. By manipulating the plug 33 uid under pressure is admitted to the power chamber 23 for actuation =of piston rod 21 and pistons 28, 29, and 30 to cause displacement of fluid between chambers 24 Vand 25 and the .cylinders 8 and 8' rpectively,

for actuating the pistons and piston rods in said cylinders simultaneously to raise and lower the implement.

In Figures?, 8, and 9, the hydraulic system is Vvalve plug 33 is manipulated as shown in Figure 8 to direct the uid from pump 31, through conduit 39, port 43 in plug 34, port 40, port 4 3 in plug 33 and port or conduit 46 to the power chamber 23 of master cylinder 22, causing the piston rod to move in direction of arrow 41 forcing the uuid ahead of piston 2s thrbugn port or conduit .45, return port 43' in plug 33 Vand conduit 42l into tank 36.

- The movement of piston rod 21 causes uidin chambers 24 and 25 to be directed to cylinder 8 and 8' through conduits 48 and 48' respectively.

causing piston rods I5 and I5 to move inf-direction of arrows 49 thereby raising the implement. By Amanipulating plug 33 to direct Ythe iluid through port or conduit 45. to the opposite endV of greater resistance I meting fluid from the 'bution of pressures to both piston rod 21 between pistons28 and 29 is larger y in diameter than the portion between the pistons 28 and 38. The reason for this variation in diameters is to effect an equal volumetric displacement of iiuids between chambers 24 and 25 and the cylinders 8 and 8', respectively, so that the movement of the piston rods I5 and taneously equal. Also the lreason for providing the individual control chambers 24 and 25 and pistons 28 and 38 for cylinders 8 and 8', respectively, is tocontrol the cylinders 8 and 8 through individual iluid columns to insure equal districylinders so that the implement may be raised and lowered Without disturbing the set position of the blade regardless of any unbalanced resistances or loads.

Heretofore in implements using a pair of cylinders for controlling the degree of operation a common source of pressure was provided for actuating both cylinders. This proved to be inefectual because when one end of the blade encountered a hard spot, rock, or other obstruction,

upon being lowered into the operating position,

was oiiered to the piston controlling that side of the implement thereby retarding the action of said piston and accelerating the action of the other piston consequently tilting the blade. Later a countershaft with bell cranks connecting the cylinders to the implement was provided which raise and lower the blade and maintain its set position regardless of any unbalanced load or resistance, vbut impossible to tilt the blade byE means of the same cylinders consequently it was. necessary to provide an independent vtilting devicewhich naturally increasedvconsiderably the .cost of manufacture.v j

In the present hydraulic control system a very simple arrangement of ports is provided for di-g valve chamber 38- tov the cylinders 8 and 8 to actuate the pistons 21| and' 2l and piston rods I5 and I5' in opposite direc- 'of cylinder 8 and through tions for tilting the blade I.

One side o! the valve chamber 38 communicates through the'port vor conduit 5I with conduit 58l the port or conduit 52 with conduit 48' of cylinder 8'. 4The opposite side `of valve chamber 38 the port or conduit 53 with the conduit 48 of cylinder 8 and with the conduit 58' ofcylinder 8'.

when' 1t is desiree, to tilt the made l so that the right Aside oi' same is raised and the left side lowered the plug 34 Figure 9 to direct the iiuid through port or con-- duits 5I and conduit 58 to the cylinder 8 as indicated by arrows 55 andto direct the fluid through.

port or conduit 52 and conduit 48 to the cylinder 8' as indicated by arrows 56, causingfthepisport 48, port 43 in plug 33 and conduit 42, as

indicated by the arrows 5 1 and 58 respectively.

By manipulating .the plug 34 to direct the fluid 58' and thereby f in any of its operative or inoperative positions and lowered without disturbing.

I5' is simulmade it possible rto .valve chamber 38 on the :through conduit e1, -r sa communicates through through-the port or lconduit si.

is manipulated as shown in ports or cond to ports or conduits 53 and 54 the blade I may be tilted in the opposite direction.

By means of this system the blade may be tilted it may be raisedand the set position regardless of any unbalanced resistance or load.

To relieve excess pressure beyond a predetermined point within the system a pop-ofivalve 58 is interposed in conduit 58 connecting the pressure side of pump 31.to tank 36.

When the control system is used on an implement connected to the draw bar 4 of the tractor, as depicted in Figures l and 2 the implement and blade may be tilted withoutitwisting strainson pusher arms 2 by virtue of the centrally located draw bar hitch 4' which permits the draw bar 4 to tilt with the implement. Howevenwhen the vimplement is connected to the tracklayer frames B as shown in Figures 10, l1, and 13 the implement and' blade cannot be tilted without exerting twisting strains on the pusher arms 2a and blade I, therefore, auxiliary hydraulic jacks 1 and 1' are provided at the ends of pusher arms 2a.to automatically raise and lower same as. re-

. quired in tilting the implement.

The hydraulic jacks 1 and 1' are mountedon brackets 6I which are secured in any suitable mannerto thetracklayer frames Ii. The piston rods 52 and 52' of the jacks 1 and 1' are pivotally connected, as at 53, to the ends 'of pusher arms 2a. The side walls v54 01E-,brackets 6I have the vertically elongated slots 55 which operatively engage the rollers 66 at the ends of pusher arms 2a. The slot and 'roller connections 65 and 65, respectively, permit vertical movement ,of the pusher arms 2a`upon actuation of jacks 1 and 1' in addition to eilecting a sturdy thrust connection for longitudinal pushing of the implement.

The hydraulic jacks are connected to tilting side where ports or conduits 5| and 52 communicates with said chamber,

and conduit 69 and 18 leading tothe top and bottom of the jacks .'I and 1', respectively. On the opposite side of chamber 38 where ports or conduits 53 and 54 communicate with said chamber is another conduit 1I which leads through T 12, conduits 13 and'14 to the bottom and top of jacks 1 and 1' respectively.

.g In Figure I4 the control system in combination y with the hydraulic jacks is diagrammatically illustrated and shows the plug valve 34 in position for 'directing the fluid to ports or conduits 5I 52 to tilt' the implement as has been described above. The port 43 of plug 34 also directs the fluid through conduit 51 and conduits 69 and 18 to the top and bottom of jacks 1 and4 1', respectively, in opposite directions, as indicated by arrows 15. It will be noted that the cylinder 8 and hydraulic jack 1 control the left side vof the implementl and cylinder 8' and hydraulic jack 1 the right side and inasmuch as each cylinder and its corresponding hydraulic jack operate in unison '-,onepusher arm 2a is raised and the other lowton r ds I5 and I5' to move in the opposite direetiorag indicated by the dotted arrows 51.

ered parallel to the horizontal line for tilting the blade thus eliminating. bending and twisting strains.

By positioning plug 34 to direct the iiuid to 'ts 53 and 54 and conduit 1I the tilting of the implement will be reversed.

A modied form of the hydraulic control system shown diagrammatically in Figure 15 illustrates how the raising vand lowering valve and the to-actuate the piston rods 62 and 62'l and tilting valve may be connected wlth the control cylinders to eliminate the master cylinder 22 and still render the system capable of performing the same functions.

The suction side of pump 31a is connected to tank 38a through conduit 44a and the pressure side of pump 31a is connected to the'tilting valve 18, then through conduit 48a to the raising and lowering valve l1 and then through conduit 42a to tank'lia to circulate the fluid through the valves and the tank when said valves are in the neutral position. The pressure relief valve 59u is interposed in conduit 60a which connects the pressure side of pump 31a with tank 36a to relieve excess pressure, beyond a predetermined point, in the system, as shown and described in the preferred form.

When the raising and lowering valve TI isin the position shown in lgure the iiuid is directed from pump 31a through conduit 39a, tilting valve 16, conduit 40a, raising and lowering valve 'Il and conduit 18 to cylinder 19 causing piston 80 to move in direction of arrow 8|. The uid expelled from cylinder 'I9 by means of piston 80 is directed through conduit A82, valve Tl and conduit 83 to cylinder 84 causing both'cylinders to operate simultaneously in direction of arrows 8l and 8|' for lowering the implement. The uid expelled from cylinder 84 by means of piston 85 is directed through conduit 86 valve Tl and conduit 42a to tank 38a. The direction of iuid for lowering the implement is indicated by means of arrows 8l. a

By manipulating the valve 90 degre the direction of ilulvd within the system will be re-rversed causing pistons 80 and 85 within cylinders 19 and 84 to move in the opposite direction for raising the implement.

It will be noted that the cylinder I9 is slightly larger in diameter than the cylinder 84; this is to equalize the area of the' piston rod end of cyl- Vinder 19, and the opposite end of cylinderV 8 4 so that there is equal volumetric displacement of iiuid between said ends of the cylinders for simultaneously equal movement of pistons 88 and 85.

One side of the tilting valve 'I6 communicates with conduit 'I8 through conduit 88 and with conduit 86 through conduit 85, the opposite side of the valve communicates with conduit 83 through conduit 98 and with conduit 82 through conduit 9|. Y

When it is desired to tilt the blade by raising the left side and lowering the right side of the implement the valve 'I6 must be manipulated to direct the uid from duits 89 and 86 to cylinder 84 causing the pistons 80 and 85 and the piston rods 8l' and 85' to move simultaneously in opposite directions as indicated by the dotted arrows 8 2. The iiuid expelled by pistons 88 and 85 is from cylinder 18 and 84 through conduits 82; and 8|, and conduits.

vcausing the blade to tilt in the opposite direction.

Having thus described ourrinventionwe claim: 1. A trail builder, in combination with a tractor, comprising a pair of forwardly extending pusher arms connected to the tracklayer framesnduit 39a through conduits 88 and 18 to cylinder I8 and through conof saidtractor, a scraping implement on the f orward ends of said pusher arms, hydraulic ja :ks mounted on said tracklayer frames, bell crank means for connecting said hydraulic jacks to said scraping implement, plunger means `for actuatingveach hydraulic jack through an individual column of iluid, hydraulic means for actuatingsaid plunger means.

2. In a trail builder comprising a tractor, a

pair of forwardly extending pusher arms, vertically slidable means for connecting said pusher arms to the tracklayer frames of said tractor, a pair of primary hydraulic jacks associated with said vertically slidable connections for vertical adjustment of the rear ends of said pusher arms, a pair of secondary hydraulic jacks mounted on the tracklayer frames of said tractor, means for associating said secondary hydraulic jacks with said pusher arms for vertical adjustment of the forward ends of said pusher arms, a pair of` valves for controlling said primary and secondary jacks, each valvecontrolling one primary jack and one secondary jack in unison.

3. A trail builder, in connection with a tractor, comprising a pair of forward-extending pusher arms connected to said tractor, a scraping element at the .forward ends of said pusher arms, hydraulic jacks mounted on said tractor and operatively engaged with said pusher arms and scraping. element, plunger means for actuating each hydraulic jack through individual columns of fluid, hydraulic means for actuating said plunger 11183115.

4. A trail builder, in combination with a tractor, comprising a pair of pusher arms, a pair of hydraulic jacks mounted on said tractor, arranged to adjust the forward ends of said pusher arms vertically, plunger meansv for actuating each hydraulic jack through individual columns pf iiuid, hydraulic means for actuating said plunger means, a pair of hydraulic jacks mounted on said tractor, arranged toadjust the rear ends of said pusher arms vertically, valve means for controlling the vertical adjustment of. the rear ends of said pusher arms. v

5. A trail builder, incombination with a tractor, comprising a pair of pusher arms connected Vto said tractor and a blade on said pusher arms,

a multiplicity of hydraulic jacks .mounted on said tractor and operatively associated with said pusher arms and blade, plunger means for actuating each hydraulic jack' through individual columns of iiuid, hydraulic means'for actuating said plunger means, valve means associated with said plunger, a` plunger actuating. means to actuate said jacks in onedirection simultaneously to raiseor lower .the blade and valve means to actuate said jacks in opposite directions simultaneously to tilt said blade.

6. In combination with a tractor, a trail builder comprising a pair of. pusher arms connected to said tractor and a blade on) said pusher arms, hydraulic jacks mounted onrsaid tractor and operatively associated with said pusher arms and blade, plunger means for directing an'individual column of uuid to each afraid4 jacks'hydraulic pressure means for actatingsaid plunger means, valve means -fordirectingrindividual columns of'lluid to said jacks for simultaneous operation ineither direction to raise and lower said blade and valve means for directing .the uid to said jacks for 'simultaneous operation in'opposite directions for tilting said blade.

7. In a'trail builder as described in claim 6,

in Vwhich thepllmger means comprises a ,cylinder containing a pressure chamber for each hydraulic jack and a power chamber, each chamber arrangedin tandem on a common piston rod, a pump to suply liluid under pressure to said power chamber, valve means for controlling the uid under pressure from said pump to said power chamber, fluid conduits from. said pressure chambers'to said hydraulic jacks. V

8. In combination with a tractor, a trail builder comprising a .pair of pusher arms connected to said tractor and a blade on said pusher arms, a pair of hydraulic jacks mounted at the side of said tractor and operatively associated with said pusher arms and blade, plunger means for directing an individual column oi uid to each of said jacks, hydraulic means for actuating said plunger means, v.valve means larranged for controlling said iacks to raise, lower and tilt said blade.

9. In a trail builder as described in claim 8 in which the plunger means comprises a cylinder containing a pressure chamber ior each hydraulic jack and a power chamber, a piston in each chamber arranged in tandem on a common pistonrod,apumptosupplyiiuidunderpressure a piston in to said power chamber, fluid conduits from said pressure chambers to said hydraulic jacks, valve means for .directing the fluid under pressure from said pump to either end of said power chamber and thereby actuating said pistons in said pressure chambers for directing iluid under pressure to said hydraulic jacks.

10. In combination with a tractor, a trail builder comprising a pair of pusher arms connected to said tractor through a vertically movable means, a blade on said pusher arms, means mounted on said ytractor and connected to said pusher, arms and blade to control the degree of operation thereof, a pair oi hydraulic jacks mounted on said tractor and connected to said vertically movable connecting means, hydraulically controlled means associated with said Jacks to actuate saidA jacks in either direction'simultaneously for raising and lowering said pusher arms and means for actuating said Jacks simultaneously in opposite directions for tilting said pusher arms and blade. Q v

LINO. BIRD. HJWARD R BRAKE. 

